HOLO Audio Spring DAC - R2R DSD512

[GUTB]

Isn't it common knowledge that digital signal attenuation is worse than analog control -- and the reason why virtually every high end DAC with a volume control uses analog?

[Miska]

4 hours ago, GUTB said:

Isn't it common knowledge that digital signal attenuation is worse than analog control -- and the reason why virtually every high end DAC with a volume control uses analog?

 

No, that is certainly not true. Good digital attenuation has SNR way beyond what is possible in analog domain. Putting volume control on your analog signal path will only increase noise.

 

[barrows]

11 hours ago, wouterk said:

Please don’t - I chose the Spring for it’s sound quality- any items interfering in the signal path are therefore not ‘a good idea’.

A well implemented volume control at full scale does nothing to alter the signal path, there are no worries here.

[barrows]

10 hours ago, GUTB said:

Isn't it common knowledge that digital signal attenuation is worse than analog control -- and the reason why virtually every high end DAC with a volume control uses analog?

No, this is a myth.  And, when considering digital volume control, at full scale, it is not "there" at all.  In other words, there is no compromise having a digital volume control at all for those who duo not use it.

[elcorso]

2 hours ago, barrows said:

No, this is a myth.  And, when considering digital volume control, at full scale, it is not "there" at all.  In other words, there is no compromise having a digital volume control at all for those who duo not use it.

 

Then, where you attenuate the volume?

 

From A+ & Hq Player (the two players I use) there is availability for software volumen control.

 

From my own experience the analogue volume control in a very good preamp is the most expensive part !

 

My only and main fear is to destroy the speakers using digital control, because it is easier and more practical through a preamp. I know that this is a very discussed topic previously, but it is worth analyzing it again!

 

A question to @Miska too ...!!!

 

Best,

 

Roch

[Miska]

1 minute ago, elcorso said:

Then, where you attenuate the volume?

 

From A+ & Hq Player (the two players I use) there is availability for software volumen control.

 

From my own experience the analogue volume control in a very good preamp is the most expensive part !

 

My only and main fear is to destroy the speakers using digital control, because it is easier and more practical through a preamp. I know that this is a very discussed topic previously, but it is worth analyzing it again!

 

A question to @Miska too ...!!!

 

It is valid concern to be afraid of accidents with digital volume control.

 

In optimal case, you don't need to use high attenuation followed again by high gain in the power amp. It is just bad for overall signal fidelity to do a lot of back-and-forth changes. Typical power amp gain is around 36 dB. If your volume in pre-amp is set to about same figure, the combination is unity-gain and there's no point on the whole exercise. For example Benchmark AHB2 has a switch to control sensitivity of the amplifier, so you wouldn't need much attenuation preceding the power amp's gain.

 

So usually best compromise is to use some sort of combination, if there's no way to control sensitivity of power amps. My recommended approach is:

 

1) Set digital volume control to maximum setting (like -3 dB) and play loud sounding music.

2) Then turn up the analog volume control to maximum level you would ever use for listening.

3)  Adjust digital volume to comfortable listening position.

 

This should give you fairly optimal SNR result with convenience and safety. You can then tune the analog volume setting over time to more suitable if necessary, while keeping it within safe boundaries. Likely your digital volume control range will then vary between something like -20 dB to 0 dB.

 

 

[GUTB]

Okay I never tried running my X20U directly into my new monos (Lindenberg Allegro). I’m currently using a Mjolnir 2 (my favorite Schiit headphone amp) running Bugle Boys as a preamp as a stand-in while I figure out a good preamp setup. My prior experiences with the X20U’s digital volume control was bad — reduced SQ. The X20U seems to use the 9018’s volume control module.

 

So because of strong claims made in here, I tried pulling out the Mjolnir and plugging the X20U directly into the Allegro. The X20U is hardware balanced so there should be no SE summing/combining/whatever involved anywhere in this chain. Also, the Allegros are only 50 watts so they don’t need a lot of attentuation to achieve a good listening volume, generally around -5 to -8 dB.

 

Soundstage seems to have narrowed and depth is sometimes harder to ascertain. Emotional engagement seems to have been completely sucked out. There is a piercing digital glare in the upper-mids / low highs that’s very annoying in some tracks — what I recall from headphone listening with the X20U. These observations may be in my head so next step is to put the Mjolnir back in to see if my observations change. Maybe the Mjolnir and its premium NOS tube stage is hiding the Sabre’s glare and adding layer of fluffy tube euphonics.

[barrows]

16 minutes ago, GUTB said:

Okay I never tried running my X20U directly into my new monos (Lindenberg Allegro). I’m currently using a Mjolnir 2 (my favorite Schiit headphone amp) running Bugle Boys as a preamp as a stand-in while I figure out a good preamp setup. My prior experiences with the X20U’s digital volume control was bad — reduced SQ. The X20U seems to use the 9018’s volume control module.

 

So because of strong claims made in here, I tried pulling out the Mjolnir and plugging the X20U directly into the Allegro. The X20U is hardware balanced so there should be no SE summing/combining/whatever involved anywhere in this chain. Also, the Allegros are only 50 watts so they don’t need a lot of attentuation to achieve a good listening volume, generally around -5 to -8 dB.

 

Soundstage seems to have narrowed and depth is sometimes harder to ascertain. Emotional engagement seems to have been completely sucked out. There is a piercing digital glare in the upper-mids / low highs that’s very annoying in some tracks — what I recall from headphone listening with the X20U. These observations may be in my head so next step is to put the Mjolnir back in to see if my observations change. Maybe the Mjolnir and its premium NOS tube stage is hiding the Sabre’s glare and adding layer of fluffy tube euphonics.

Sabre chips do not have "glare" inherently, unless the implementation is poor.  And the ESS 9018 volume control is superb.  The only drawback when using a well implemented digital volume control is if you need a ton of attenuation.  The ESS 9018 volume control is entirely transparent if used sparingly.  As I recall it operates at 32 bits, so even with a 24 bit file (and one's system only really achieves at most 18 bits of resolution in room) you have 8 bits of volume control with no loss of resolution.  8 bits of volume control yields about 48 dB of attenuation, so even allowing for some error here, you can attenuate a lot with the ESS volume control without any degradation.  How much attenuation are you using?  If you need more than -20 dB (<4 bits) for reference listening levels you have very poor gain matching in your system and that should be addressed (with gain matching like this you are losing resolution no matter what you use for VC).

As Jussi (miska) notes, many systems are subject to poor gain matching and are throwing away resolution, analog or digital VC in this case is no matter, lots of analog attenuation adds noise as well.

If you are adding a preamp to add color to the sound that is another story, but it has nothing to do with whether a digital volume control is transparent or not...

[GUTB]

Well, putting the Mjolnir back in...yeah, the difference is huge. Digital volume control is in fact embarrassingly bad, or the the preamp stage is just a massively improvement. I noticed higher resolution when using the digital volume -- things like recording room echo was more obvious, hard Ps, etc. But relying on the X20U was like watching a scene through a viewport, while the Mjolnir was more like standing in the venue, much wider and imaging more solid / deep. Bigger. The edge is taken off the glare.

 

Am I doing something wrong, or is this a case of people who've never heard high end audio?

[pkane2001]

1 minute ago, GUTB said:

Am I doing something wrong, or is this a case of people who've never heard high end audio?

 

You’re doing something wrong.

 

[GUTB]

Just now, pkane2001 said:

 

You’re doing something wrong.

 

 

Some recommendations please?

[pkane2001]

Try HQPlayer for volume control. Set X20U volume to 0dB.

 

My x20pro sounds amazing with no preamp. So does Holo Spring. I also use both without a headphone amp with HD650s in balanced mode — also great sound.

 

Just be careful about the HQP volume control, it’s easy to set it to maximum without intending to.

 

[GUTB]

OKAY GUYS TIME TO GET REAL:

 

Some months ago I asked about DSD512 support for XMOS. I was told very clearly that it's here via firmware already. So my question is...where's the firmware? I see that Holo is selling an upgraded SU-1 for which you need to email to get the specific drivers that will support 512. Okay. But for XMOS at large? No information AT ALL. Only that u216 board on diyaudio which does not look like it's a plug-in replacement for the standard 208 / Amanero boards out there. 

 

So, does XMOS finally have DSD 512 and no one has updated their eBay descriptions yet...or what? Is the Holo upgraded SU-1 the only option for 512 on XMOS?

[ted_b]

Get real?  Huh?  DSD512 native has been available since my Spring review many months ago.  Get the proper firmware and drivers from your manufacturer or dealer.  If you bought from Tim, have him send it.  I listen to DSD512 via Linux (microRendu) and via Windows 10 (ASIO driver).  So do most other Holo owners (and other XMOS dacs like ifi, etc).  The dac needs to be DSD512 capable, not just the DDC (if used).  Are you saying we are lying (as you are apt to say around here)?

[lmitche]

The IFI microIDSD is an Xmos DAC and does DSD512 beautifully. I read that IFI developed their own Xmos drivers.

[guymrob]

On 29/10/2017 at 5:02 PM, Miska said:

 

No, that is certainly not true. Good digital attenuation has SNR way beyond what is possible in analog domain. Putting volume control on your analog signal path will only increase noise.

 

No necessary, a good designed analog volume control still out perform a digital ones. Also it is difficult to do a DSD signal attenuation in digital domain. You can read from ESS Tech

 

[guymrob]

18 hours ago, barrows said:

Sabre chips do not have "glare" inherently, unless the implementation is poor.  And the ESS 9018 volume control is superb.  The only drawback when using a well implemented digital volume control is if you need a ton of attenuation.  The ESS 9018 volume control is entirely transparent if used sparingly.  As I recall it operates at 32 bits, so even with a 24 bit file (and one's system only really achieves at most 18 bits of resolution in room) you have 8 bits of volume control with no loss of resolution.  8 bits of volume control yields about 48 dB of attenuation, so even allowing for some error here, you can attenuate a lot with the ESS volume control without any degradation.  How much attenuation are you using?  If you need more than -20 dB (<4 bits) for reference listening levels you have very poor gain matching in your system and that should be addressed (with gain matching like this you are losing resolution no matter what you use for VC).

As Jussi (miska) notes, many systems are subject to poor gain matching and are throwing away resolution, analog or digital VC in this case is no matter, lots of analog attenuation adds noise as well.

If you are adding a preamp to add color to the sound that is another story, but it has nothing to do with whether a digital volume control is transparent or not...

 

You can read this article on ESS Tech

 

digital-vs-analog-volume-control.PDF

 

[barrows]

1 hour ago, guymrob said:

No necessary, a good designed analog volume control still out perform a digital ones. Also it is difficult to do a DSD signal attenuation in digital domain. You can read from ESS Tech

You are mis-representing the ESS dissertation.  This is only true at very high rates of attenuation.  Pay attention to the details here!

 

As long as attenuation is not too high, well implemented digital volume control wipes the floor with any analog approach.

 

Additionally, at very low listening levels (the only place where analog VC could have an advantage) the low level details which are missing are not audible anyway in any real world system, as they would be well below the noise floor and the threshold of audibility.

 

Unless you have a system with really poor gain matching, requiring more than 40 dB of attenuation for reference listening levels, the ESS volume control is transparent.

 

Stop spreading myths.  Please.

[R1200CL]

http://www.digitalaudioreview.net/2013/12/kih-3-can-digital-volume-controls-keep-it-honest/

 

http://thewelltemperedcomputer.com/Intro/SQ/VolumeControl.htm

 

 

[barrows]

Final word on digital volume control:  If one believes that digital volume control has problems, then you might as well forget about listening to recorded music as well, as all (with the exception of some very unusual audiophile recordings) recorded music is mixed in the digital domain these days with digital level corrections made, including things like Jared Sachs wonderful Channel Classics releases...

[ted_b]

Barrows, not to debate digital volume, but you brought up Jared.  Most of the time he does an analog mix at the session, prior to ADC, so there is no digital volume being used.  If the session is complex then yes DXD edits and sweetening might be needed post-production.  It's not the rule, though.

[barrows]

2 minutes ago, ted_b said:

Barrows, not to debate digital volume, but you brought up Jared.  Most of the time he does an analog mix at the session, prior to ADC, so there is no digital volume being used.  If the session is complex then yes DXD edits and sweetening might be needed post-production.  It's not the rule, though.

Thanks Ted, that is what I meant, DXD/Pyramix in post production, right?

[ted_b]

24 minutes ago, barrows said:

Thanks Ted, that is what I meant, DXD/Pyramix in post production, right?

Yes but he strives to stay away from any of that if possible.

 

Back on topic, I have heard really good and not so good digital volume controls (and same can be said for analog ?).  My best example of the positive is when I decided to rip out the multichannel analog preamp I was using and let my exaSound e28 do the work (channel trims and master volume); huge difference, but then again I removed several pounds of 5.1 interconnect too.  And the Sony TA-P9000 was not a SOTA preamp either.

 

I run 2 channel through a hi end analog pre currently, but most of the reasons have to do with impedance and tonality issues more than noise.  My soundstage is black.

[GUTB]

To those who claim digital volume controls beats analog, some questions:

 

1. How would you describe the spaciousness of image? Please be specific.

2. How would you describe the soundstage? Please be specific.

3. What is the level of emotional engagement?

 

For example, my system using Sabre volume control would be described this way:

- Image depth seems to be shallow and I have some difficulty with determining placement.

- Soundstage is narrow, seems to fall on the inside edge of my speakers and focus more towards the center.

- Emotional engagement is gone. I feel no desire to physically respond to the music (air guitar, bob head, pretend conductor, etc).

[franz159]

A reminder to ALL:

  the title of this thread is "HOLO Audio Spring DAC - R2R DSD512"

 

Could you please refrain from continuously high-jacking the original purpose of this thread with this conversation on digital vs analogue volume control?

 

Please open (yet another) specific thread to discuss this if you are inclined to do so, but please please please allow this thread to evolve around its original intended topic.